Preview

General Chemistry Chapters 19, 21, 22

Satisfactory Essays
Open Document
Open Document
1188 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
General Chemistry Chapters 19, 21, 22
HOMEWORK EXAM 3:

Chapter 19:

The half life of 90Sr is 29 years. What fraction of the atoms in a sample of 90Sr would remain 175 years later?
Answer

0.166

0.125

0.062

here
0.015

Which relation is not correct?
Answer

11p = 11H = proton

0-1e = 0-1β = electron

here
+10e = +10β= positron

10n = neutron

As a result of beta decay, the product nucleus is
Answer

one atomic number lower than the original element.

two atomic number higher than the original element.

here one atomic number higher than the original element.

two atomic number lower than the original element.
What is X for the nuclear reaction: 21284Po à 20882Pb + X
Answer

42p

1-1β

here
42α

11n

Which statement is not correct for the nuclear reaction: 146C à 147N + 0-1β ?
Answer

C is radioactive.

Nucleus of C is not stable.

Here?
N lies above the belt of stability of nucleus.

One neutron in the nucleus of C converts to a proton with the release of the release of particle.

If 12% of a certain radioactive isotope decays in 5.2 years, what is the half-life of this isotope?
Answer

0.59 yr

1.7 yr

21.7 yr

here
28.1 yr

Which statement is false?
Answer

No chemical treatments can make radioactive elements harmless.

The rate of decay (disintegration) of U-238 is proportional to its sample size.

Changes in temperature or pressure cannot affect the rate of decay (disintegration) of radioactive elements.

F
Decay constant maintains its constancy only at the specific temperature.

How much energy is lost or gained when a mole of cobalt-60 undergoes beta decay:
6027Co --> 6028Ni + 0-1e ?
The mass of the 6027Co atom is 59.933819 amu, and that of a 6028Ni atom is 59.930788 amu.
Answer

Here?
2.724x1011 J energy is released.

2.724x1011 J energy is absorbed.

2.724x108 J energy is released.

You May Also Find These Documents Helpful

  • Good Essays

    Nt1310 Unit 6

    • 2053 Words
    • 9 Pages

    A nucleus of the nuclide 241Pu decays by emission of a β-particle followed by the emission of an 94 α-particle. Which of the nuclides shown is formed? A…

    • 2053 Words
    • 9 Pages
    Good Essays
  • Good Essays

    82. An alpha particle is a helium atom with a 2+ charge, a beta particle is an electron with…

    • 373 Words
    • 2 Pages
    Good Essays
  • Good Essays

    F331 Revision

    • 1350 Words
    • 8 Pages

    iii. An isotope should have a half-life which is neither too short or it will decay before tracing is complete. nor too long or it will persist for too long in the body, potentially causing harm to the patient.…

    • 1350 Words
    • 8 Pages
    Good Essays
  • Good Essays

    Nt1310 Unit 6 Study Guide

    • 1897 Words
    • 8 Pages

    |element to 12C isotope. | |Explain that atomic masses are relative to | | |…

    • 1897 Words
    • 8 Pages
    Good Essays
  • Good Essays

    Chemistry Copper Lab

    • 7450 Words
    • 30 Pages

    2. The mass of a proton is approximately equal to the mass of a neutron.…

    • 7450 Words
    • 30 Pages
    Good Essays
  • Good Essays

    Lab 7

    • 995 Words
    • 4 Pages

    d. How well does each flip (or half-life) actually eliminate half of the remaining parent isotopes?…

    • 995 Words
    • 4 Pages
    Good Essays
  • Powerful Essays

    Virtually all the mass of the atom is concentrated in the nucleus, because the electrons weigh so little.…

    • 887 Words
    • 8 Pages
    Powerful Essays
  • Good Essays

    3. Explain which would be the best isotope from the Isotope Half-Life Chart to measure a 3 billion year old specimen.Rubidium isotope would be the best isotope to use for that measurement because it contains the most years that would be needed to measure that span. Even with the help of this isotope the task would still be rather difficult to make precise.…

    • 555 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Biology: Key Questions

    • 665 Words
    • 3 Pages

    2. Given that the half-life of the radioisotope carbon-14 is 5730 years, how useful do you think this isotope would be for dating bones that are over a million years old?…

    • 665 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Lab Report

    • 623 Words
    • 3 Pages

    The isotope 14C differs from 12C in that 14C has (pick one of the following)…

    • 623 Words
    • 3 Pages
    Good Essays
  • Satisfactory Essays

    astro quiz

    • 682 Words
    • 4 Pages

    Suppose you find a rock that contains 10 micrograms of radioactive potassium-40, which has a half-life of 1.25 billion years. By measuring the amount of its decay product (argon-40) present in the rock, you conclude that there must have been 80 micrograms of potassium-40 when the rock solidified. How old is the rock?…

    • 682 Words
    • 4 Pages
    Satisfactory Essays
  • Good Essays

    Awesom

    • 1351 Words
    • 6 Pages

    The first decay processes to be discovered were alpha decay, beta decay, and gamma decay. Alpha decay occurs when the nucleus ejects an alpha particle (helium nucleus). This is the most common process of emitting nucleons, but in rarer types of decays, nuclei can eject protons, or specific nuclei of other elements (in the process called cluster decay). Beta decay occurs when the nucleus emits an electron or positron and a type of neutrino, in a process that changes a proton to a neutron or the other way around. The nucleus may capture an orbiting electron, converting a proton into a neutron (electron capture). All of these processes result in nuclear transmutation.…

    • 1351 Words
    • 6 Pages
    Good Essays
  • Satisfactory Essays

    Marriott

    • 655 Words
    • 3 Pages

    rD = rf + MRP * βD = 8.95% + 3.06% * 0.3595 = 10.05%…

    • 655 Words
    • 3 Pages
    Satisfactory Essays
  • Good Essays

    Nuclear Chemistry

    • 686 Words
    • 3 Pages

    The decomposition of the nucleus is referred to as radioactive decay. During radioactive decay, an unstable nucleus spontaneously decomposes to form a different nucleus, giving off radiation in the form of atomic particles or high energy rays in an attempt to reach a more stable arrangement of its protons and neutrons .This decay occurs at a constant rate that is referred to as half-life. The stable nuclides exist in the zone of stability. A radionuclide that decays to another nuclide which may be either radioactive or stable is a parent nuclide; while a daughter nuclide is formed by the radioactive decay of a different nuclide. Radioactive nuclei can undergo decomposition in a variety of ways. The spontaneous decay process can produce particles as in the case of alpha, beta, or positron emission. The alternate form of emission is that of electromagnetic radiation such as x-rays or gamma-rays. An alpha particle is simply a helium nucleus which is ejected with high energy from an unstable nucleus. Beta particles are identical to electrons and thus have a negative charge. This type of decay process leaves the mass number of the nuclei unchanged. Positron is the opposite of beta decay. A ramification of alpha or beta particle production is that the newly formed nucleus is left in a state of excess energy. A way for the nucleus to release this excess energy is by emitting gamma rays. Since gamma rays have no mass, and are waves rather than particles, the elements atomic number does not change…

    • 686 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Nuclear Power - Pros

    • 717 Words
    • 3 Pages

    atomic nuclei join together, or "fuse", to form a single heavier nucleus. This is usually accompanied by the release or absorption of large quantities of energy. Fusion is also found in the process that powers active stars, the hydrogen bomb.…

    • 717 Words
    • 3 Pages
    Good Essays